plasmid isolation problem HELP! - (Dec/01/2008 )

I'm having problems isolating my plasmid in miniprep also maxiprep. My plasmid is pML7 (pmon17336) and i'm using E.coli glg C (-) for transformation.As i got colonies after my cloned product transformed E.coli glg C (-) (i also tried DH5 alfa) i confirmed my insert by colony PCR(Lysate PCR). But when i tried to extract Plasmid by Alkali Lysis method i get plasmid in very high band after elctrophoresis. i tried to double digest it 1ul didn't work but 10ul worked.then i tried maxi prep i didn't get any thing.what must i do? please someone help.

by the way my plasmid resisted to spectinomycine /streptomycine.i'm using strep.

-naupaka-

It sounds like your extraction wasn't very good: lots of genomic DNA. Be careful with the transfer of supernatants over to the fresh tubes, also be careful with the spin steps.